Trump flags changes to skilled work visas

President Donald Trump says he is planning changes to the visas issued temporarily to highly educated immigrants so they can work in specialty occupations, including citizenship.

He flagged the changes to the H-1B visas would create simplicity, certainty and a possibility that the workers could become US citizens.

"H1-B holders in the United States can rest assured that changes are soon coming which will bring both simplicity and certainty to your stay, including a potential path to citizenship. We want to encourage talented and highly skilled people to pursue career options in the US," Trump said in an early morning tweet on Friday.

Republican Trump and Democrats in the US Congress are at an impasse, as he refuses to end the longest shutdown in federal government history until he secures $US5.6 billion ($A7.8 billion) to build a wall along the country's southern border.

While Trump typically depicts undocumented immigrants and asylum seekers attempting to enter the country through Mexico as criminals and terrorists, he frequently praises those applying for H-1Bs, who must hold a bachelor's degree or higher.

Competition is tough for the temporary visas. In 2018, the US hit the limit on the number of H-1Bs it could issue, 65,000, by the first week of April, according to the Department of Homeland Security.